Apparatus and method for bulking yarn



June 21, 1966 A. BuRLEsoN 3,256,582

` APPARATUS AND METHOD FOR BULKING YARN Filed March 4, 1964 www INVENTOR /ffa/yzfffal APPARATUS AND METHUD FR BULKING YARN This invention relates to the manufacture of yarn and more particularly to method and apparatus for producing bulked yarn.

It has been fou-nd to be desirable in the production of fabric articles comprising yarn made from synthetic textile filaments and particularly those of the heat setta-ble variety, to impart curls, coils, crimps and the like to the filaments at some stage in their manufacture in order to provide desirable `blulkiness, soft texture, stretchiness and pleasing appearance to the fabric article. Y

Early efforts in producing bulked yard included time consuming batch processes in which the yarn was mechanically twisted, set and then mechanically reverse twisted. This type of process has proved unsatisfactory in some respects, especially respecting the slowness with which yarn could be -bulked, the complexity of the equipment needed and the ditliculty of producing uniformly bulked yarn on succeeding runs on the same equipment or on runs on duplicate equipment due to minor yarn tension differences between runs, surface roughness of the equipment parts and the like.

Efforts next were directed toward producing more quickly and uniformly bulked yarn by contacting the yarn while moving with a stream of fluid passing generally axially of the yarn together with heating of the yarn and in some cases the application `and removal of liquids or wet gases to the yarn.

It is an improvement of this second type of system thatv the method and apparatus of the present invention has been developed and accordingly it is an important object of this invention to provide apparatus capable of producing uniformly bulked yarn in an ei`n`ecient manner.

As used herein the term yarn is intended to apply not only only to fiber assemblies spun fr-om staple-length fibers, but also to such assemblies comprised of continuous filaments, blends of staple-length fibers and continuous filaments and to yarn consisting of a single ply or of several twisted or untwisted plies.

lt is a more specific object of the present invention to provide apparatus for bringing moving yarn and air together in a relatively narrow tube or jet, withdrawing the air circumferentially of the yarn at a point where the narrow tube suddenly increases in diameter Ithe resulting turbulence thereby effecting a curling, coiling and crimping of said yarn, and means including heating means to set the coils, crimps and curls in the yarn.

Yet another object of this invention is the provision in apparatus of the type described of means including a back pressure actuated mechanism to effect the discharge of the bulked yarn from the enlarged portion of the tube.

A further object of the invention is the provision in apparatus of the character described of novel means for bringing the air into contact with the yarn and of conducting the air and yarn to the bulking zone of the apparatus, said means including a container enclosing the prebulked yarn and including an air inlet to the container and a yarn and air inlet to the bulking zone.

' Although air is disclosed herein `as the preferred means for carrying the yarn to the 'bulking zone, it should be realized that `air including water vapor to a greater or lesser degree and at temperatures other than ambient are envisioned within the meaning of the terminology employed.

' States Patent O ACC The objects set forth as well as other objects that will become apparent hereinafter will be more readily understood from -a reading of the following detailed discussion having reference to the `attached drawing in which a pre- `ferred illustrative embodiment of apparatus characterizing the principles of the invention is set forth and in which a particular example is given, not to limit the scope and applicability of the invention, but only so that its principles might be more lucidly presented.

In the drawing:

The figure is a generally schematic elevational view of a preferred form of apparatus embodying principles of the invention, `with portions sectioned and broken away to illustrate features that would not otherwise be apparent.

Now with more particular reference to the drawing, lapparatus for bulking yarn is shown at 10. The apparatus 10 includes an enclosed pressurizable chamber or receptable 12 configured and dimensioned such as to receive and support at least one wound package 14 of yarn wi-thin the receptacle. As shown the package 14 is supported on a platform 16 which may be suitably journalled las to be rotatable `with respect to the receptacle depending somewhat on the `manner in which the yarn is wound and the ease with which the yarn can be generally axially withdrawn from the package Ias will become apparent hereinafter.

The receptacle 12 includes suitable hatch means (not shown) for use in placing packages 14 in position as shown and removing the spent package cores. Also communicating with the interior of the receptacle 12 are an air inlet conduit 18 through which pressurized air is introduced to the receptacle and an outlet conduit 20 through which yarn and air pass toward the crimping zone 22.

A tube 24 is secured to the outlet conduit 20 as by threading thereinto at 26 so as to extend outwardly from said conduit. As shown the tube has a shorter portion 28 having a relatively narrow interior diameter defining the throat of a jet 30 and a longer portion 32 having a relatively broad interior diameter defining a passageway 34 which is open at the outer, free end 36 thereof. According to the present invention the interior diameter of the tube 24 suddenly increases between the portions 2S and 32 as at 38 and a plurality of circumferentially spaced, generally radially extending openings 40 are formed through the tube 32 closely adjacent the diameter enlargement point 38 and are oriented so as to communicate the larger interior diameter passageway 34 with the exterior of the apparatus for the escape of pressurized air from thev apparatus as explained hereinbelow. p Suitable heating means 42 such as steam coils, hot gas conduits or electrical resistance wires are preferably disposed circumferentially about a portion of the tube section 32 intermediatethe openings 40 and the free end 36 to heat set the coils, crirnps and curls formed in the yarn Within the bulking zone 22.

The apparatus of the present invention also preferably vincludes a novel back pressure actuated mechanism 44 for effecting a uniform rate of Withdrawal of bulked yarn from the passageway 34. The yarn withdrawing mechanism 44, as depicted, includes a collar 46 which reciprocably circumferentially engages the tube 24 near the free end thereof and carries a plurality of flat spring leaves 48 at its axial outer end 50. The springs 48 extend generally axially outwardly and radially inwardly adjacent and beyond the free end 36 of the tube 24 so that the bulked yarn 52 issuing from the tube is frictionally embraced |by the inner surfaces of the spring leaves 48. Preferably the spring carrying collar 46 is arranged to be oscillated axially of the tube 24 between an upper position asshown, wherein the spring leaves closely embrace the coiled yarn 52 and a lower position wherein the engagement of the inner surfaces of the spring leaves with the outer surfaces of the tube 24 near the free end thereof combined with the pressure of the bulked yarn included between the spring forces the spring leaves to rotate them outwardly a certain extent and allow a uniform amount of bulked yarn to issue from the axially outer end of the springs. The collar 46 can be oscillated by any convenient means such as by the preferred means shown. The latter includes a suitable device such as a motor 54 for providing rotary motion which is imparted by means of the motor shaft to a cam 56 which operates on a pin 60 afixed to the collar '46. A tensioned coil spring may also be secured to the pin 60 and arranged to hold the pin 60 in operative engagement with the cam 56. Thus, as shown, rotation of the cam 56 urges the collar upwardly and as the cam 56 is rotated further the spring 58 returns the collar 46 to its lower position in a cyclic fashion.

Operation A package of yarn to be bulked is placed in the receptacle 12 and the outermost end of the yarn is threaded through the outlet conduit into the throat of the jet 30, whose diameter is slightly larger than the diameter of the yarn. The heater 42 is brought to the desired temperature and pressurized air supplied to the receptacle 12 through the inlet 18. As the pressurized air moves through the receptacle and out the outlet 20 the friction of the ai-r upon the exterior surface of the yarn will unwind yarn from the package 14 and carry the yarn continuously upwardly through the jet 30.

By virtue of the air pressure in the receptacle and smallness of the jet 30, the air and yarn travel at a high velocity through the jet. As the air and yarn emerge into the larger interior diameter passageway at 38, the resulting turbulence tends to throw the yarn into contact with the interior walls of said passageway with a spiraling or spinning motion, like a vortex. Therefore the yarn will coil and begin to become packed into the lower portion of the larger interior diameter section ofthe tube. Now, if the air were to have to travel through the packing yarn to exit from the outer end 36 of the tube 24, it can be seen that the efficiency of the system would rapidly fall off as more yarn became packed in the lower portion of the tube, eventually causing a stoppage when packing of the yarn into this lower portion reduced its capacity to let air pass therethrough and the yarn thus exerted a force equaling the pressure of -the air in the receptacle 12.

Accordingly, openings 40 have been provided closely adjacent the change in tube interior diameter at 38, small enough so that substantially all of the pressurized air but not `the yarn escapes radially of the tube at this point and the yarn continues to curl, coil, and be crimped and packed into the large diameter portion of the tube.

It has been found that usually the coiling continues in a first direction for a certain length of time and then reverses due to the fact that while it is coiling in the first direction in the bulking zone, twist is being inserted in the opposite direction in the portion of the yarn extending between the jet and the yarn package. This latter twist builds up sufficient torque to overcome the first direction coiling of the bulking yarn and thus initiates a reverse in the direction of coiling.

As the yarn is packed into the lower portion of the larger interior diameter to be sectioned by the action of the pressurized air passing through the jet, the upper extent of the packed and coiled yarn is moved upwardly in the tube and this yarn passes through the portion of the tube heated by the means 42 this heat setting the crimps, coils, and curls in the yarn. Continued operation of the apparatus moves the bulked yarn upwardly out of the heating zone toward the outer, free end 36 of the tube 24.

While most generally the bulked yarn would discharge at a uniform rate from the end 36 of the tube by virtue of the air pressure behind the bulked yarn, it has been 4. found that there are occasions when a bulked filament will become tangled and prevent discharge at a uniform rate.

Therefore, according to the preferred form of the apparatus of the invention that is shown in the drawing a back pressure actuated yarn discharge assisting mechanism 44 is positioned adjacent the tube over end. Thus, as the bulked yarn comes to the point where it can be frictionally engaged by the interior surfaces of the axial- 'ly reciprocated fiat springs 48 so that the springs alternately grasp an amount of bulked yarn and pull it upwardly thus lowering the internal pressure of the bulked yarn within the larger interior diameter section of the tube, and then somewhat relax their grasp on the yarn and allow the back pressure to push the yarn outwardly from the outer end of the flat springs as the springs are reciprocated downwardly.

The bulked yarn thus issuing at a uniform rate from the discharge assisting portion of the apparatus is collected by suit-able means not shown for further processing into fabric articles.

To exemplify the proportions of the portions of the apparatus so that the operation thereof might be more fully understood, an efficient means for coiling yarn has been found to be provided when using a tube 24 approximately 6-8 inches long and having a larger interior diameter of %2 inch. In this example, the smaller interior tube diameter or jet 30 is 8-10 times greater than the diameter of the yarn tube operated upon and 6 equally radially spaced air escape holes 40 are provided, having been lformed with a standard No. size drill (approximately 1/74 inch). The air pressure utilized in the receptacle 12 yas the yarn carrier in this example may be in the range between 20 and 65 pounds per square inch gauge and operation of the apparatus has been found to efficiently produce uniformly bulked yarn at a substantially constant r-ate of flow.

Accordingly, it should now be apparent that the apparatus of the invention eiciently accomplishes all of the objects set forth hereinabove. Also, that the embodiment and example discussed are solely illustrative of the principles of the invention and are not to be understood in a limiting sense since lthose skilled in the art will apprehend that many modifications are possible within the perview of these principles. Therefore, this invention is not to be understood as limited to the particular construction shown but limited only by the spirit and scope of the following claims.

Iclaim:

1. Apparatus for producing uniformly bulked yarn comprising: a tube having a first section of lesser internal diameter defining a jet and a second section axially adjacent said first section and having a substantially greater internal diameter; means defining at least one radially directed opening through said tube in said second section closely adjacent the juncture between the first and second sections; means for admitting a pressurized, yarn carrying fiuid to ysaid jet whereby fluid turbulence at the juncture of said sections effects a coiling, curling, crimping of the yarn and packs said yarn into the second portion of the tube and the major portion of said fluid issues from said tube through said radially directed opemng.

2. Apparatus as set forth in claim 1 wherein the pressurized yarn carrying fluid admitting means includes a pressurizable receptacle having an outlet communicated to said jet, means for supporting a yarn package within the receptacle and an inlet for admitting pressurized fluid to the receptacle.

3. Apparatus as set forth in claim 2 additionally comprising a heater circumferentially disposed about said tube intermediate the extent of the greater internal diameter section of the tube and arranged to heat-set the coils, curls and crimps in the yarn thereby bulking the yarn.

d. Apparatus as set forth in claim 2 additionally comprising means for heat-setting the crimps, coils and curls in said yarn, thereby bulking the yarn.

5. Apparatus as set forth in claim 4 additionally comprising means for withdrawing the bulked yarn from the larger internal diameter section of the tube at a uniform rate.

6. Apparatus as set forth in claim 5 wherein the bulked yarn withdrawing means are responsive to the pressure of bulked yarn within the larger internal diameter section.

7. Apparatus vas set forth in claim 4 wherein the intern-al diameter of the jet is approximately 8 times greater than the diameter of the pre-bulked yarn and the fluid pressure within the receptacle is within the range -65 lp.s.i.g.

8. Apparatus as set forth in claim 4 wherein the yarn carrying iluid is air which carries the yarn into the jet by frictional contact therewith while traveling through said jet.

9. Apparatus as set forth in claim 6 wherein the bulked yarn withdrawing means comprises a collar reciprocably mounted circumferentially of said tube adjacent the end thereof opposite from said jet, me-ans for axially reciprocating said collar at a uni-form rate and resilient means extending axially outwardly and radially inwardly from -said collar and adapted to yfrictionally engage bulked yarn emerging from said tube end.

10. Apparatus as set forth in claim 9 wherein lthe collar carrying resilient means include at spring leaves adapted to frictionally grasp the bulked yarn to a greater extent during axially outward movement of the collar and to a lesser extent during axially inward movement of the collar thereby withdrawing bulked yarn from said tube :at a uniform rate.

lll. Apparatus for producing uniformly bulked yarn comprising a tube, means for continuously forcing yarn into said tube'through `a first end thereof in a coiled and crimped manner, heating means adjacent the tube for heat-setting said crimps and coils in the yarn thereby bulking the yarn, and means for withdrawing the bulked yarn from the second end of said tube at a uniform rate, said means being responsive to the amount of bulked yarn within said tubes.

12. Apparatus as iset forth in claim 11 wherein the yarn forcing means comprises pressurized air directed into the first end of the tube and additionally comprising a plurality of generally radially directed openings formed through said tube adjacent the first end thereof, the diameter of each opening being smaller than the diameter of said yarn whereby the pressurized yair which has carried yarn into said tube escapes through said openmgs.

13. Apparatus as set forth in claim 12 wherein the internal diameter of the tube lbetween said openings and said tube first end is substantially smaller than that of the remainder of the tube, thereby defining a jet through which the pressurized air Hows at relatively high Velocity soyas to frictionally carry yarn into the tube.

14. Apparatus as set forth in claim 13 wherein the tube internal diameter shanplly increases in diameter between the jet portion and the remainder of the tube 6 whereby the turbulence created -by yarn carrying pressurized air emerging from the jet portion of the tube into the larger internal diameter portion thereof effects the crimping and coiling of the yarn.

15. A method for .producing uniformly bulked yarn including: -directinga stream of pressurized fluid axially along a length of yarn and through a constriction so that the fluid carries the yarn through the constriction; leading the fluid radially away from the yarn at a point adjacent the terminus of the constriction radially confining the yarn emerging from the constriction to limit the size of coils and curls which `are effected in the yarn .as it emerges from the constriction; heat-setting said coils and curls; and collecting the yarn so bulked.

i6. The process of uniformly bulking heat-settable yarn comprising placing the yarn in an enclosed container having an outlet including :a relatively narrow constriction; threading an end of the yarn into the outlet; introducing .a stream of pressurized fluid into the container so that it carries the yarn out of the container and through the constriction, directing the uid stream away from the yarn emerging from the constriction and confiiningthe yarn imparting increased bulk thereto; heat setting the yarn; and withdrawing the bulked yarn from confinement.

i7. The process of claim 16 wherein the pressurized fluid is air. i

13. The process of uniformly bulking heat-settable y-arn comprising blowing the yarn through a relatively narrow diameter jet into a tube having a larger diameter than the jet; with a pressurized fluid; removing most of the pressurized fluid from contact with the yarn near the point where the yarn emerges from the jet and enters the tube, thereby effecting a turbulence in the fluid stream carrying the yarn iat said point which curls and coils said yarn and packs it into said tube; heat setting the coiled, curled and packed yarn and removing the yarn from the tube.

19. A process for uniformly bulking heat-settable yarn including: directing a stre-am of fast movin-g air axially along a length of yarn so that the yarn is carried along by the stream, directing the stream of air away from the yarn at a point adjacent a yarn collecting area and collecting the yarn in a confined area at least partly bounded by a concavely curved surface so that the yarn coils and curls as it contacts said surface and is packed into said area by the air stream; heat setting the yarn in `the coiled, curled and packed condition and serially grasping portions of the yarn so bulked within said confined area and pulling them from the area at a uniform rate.

References Cited by the Examiner UNITED STATES PATENTS 2,734,228 2/1956 Hoy 28-72 2,854,701 10/1958 Rainard 28--72 2,914,835 12/1959 Slayter et al.v 28-1 3,152,379 10/1964 Osban 28-1 ROBERT R. MACKEY, Primary Examiner.

DONALD W. PARKER, Examiner.

L. K. RIMRODT, Assistant Examiner. 

1. APPARATUS FOR PRODUCING UNIFORMLY BULKED YARN COMPRISING: A TUBE HAVING A FIRST SECTION OF LESSER INTERNAL DIAMETER DEFINING A JET AND A SECOND SECTION AXIALLY ADJACENT SAID FIRST SECTION AND HAVING A SUBSTANTIALLY GREATER INTERNAL DIAMETER; MEANS DEFINING AT LEAST ONE RADIALLY DIRECTED OPENING THROUGH SAID TUBE IN SAID SECOND SECTION CLOSELY ADJACENT THE JUNCTURE BETWEEN THE FIRST AND SECOND SECTIONS; MEANS FOR ADMITTING A PRESSURIZED, YARN CARRING FLUID TO SAID JET WHEREBY FLUID TURBULENCE AT THE JUNCTURE OF SAID SECTIONS EFFECTS A COILING, CURLING, CRIMPING OF THE YARN AND PACKS SAID YARN INTO THE SECOND PORTION OF THE TUBE AND THE MAJOR PORTION OF SAID FLUID ISSUES FROM SAID TUBE THROUGH SAID RADIALLY DIRECTED OPENING. 